Method of forming shells



June 2, 1931. 3, IRELAND 1,808,731

METHOD OF FORMING SHELLS Filed April 25, 1950 2 Sheets-Sheet 1 PatentedJune 2, 1931 UNITED-STATES.

PATENT OFFICE enemas E. lawn, or TOLEDO, one, assumes; TO THE CITY mommaa root cou- 1 mm, or 10mm, 01110, A CORPORATION or OHIO METHOD OFFORMING SHELLS Application file'a April 25,

' 5 and straining of the material and without production of surfacemarks and imperfections as ordinarily result from drawing dies,

thus "leaying' .the surface smooth and unmarred and suitable for platingor other surface treatment with minimum preparation.

the metal shifts inwardly from its margins- I It has heretofore been thepractice to draw such bodies from flat sheets ofmaterial into a pan-likeform and then remove the central area to afford an open frame. In suchmethod under a contractive tension reducing the marginal contour andnecessitating an excess of material to be distributed within the diethus tending to form wrinkles and surface markin s, which imperfectionsare accentuated y the movement of the metal upon the die surface. V

In the present method the blank is formed as an endless flaring band ofmaterial, the,

2 margins of which are gripped and held under tension while pressure isapplied to the intermediate portion of the blank in a directionperpendicular to the general planeof the flaring band and inclined tothe flaring sides thereof whereby the band is expanded and stretched byinternal pressure, so forming the material into shape over a ram or formwithout the use of a corresponding matrix by a pulling tension such asto increase the extent of the marginal line and prevent formation ofwrinkles and surface markings.

One of the objects of my invention is to form a radiator shell fromsheet metal parts that are so shaped that the parts ma be integrallyconnected to form a 'blan from which the shell may be produced andthereby enable the production of radiator shells at an exceedingly lowcost. In the preferred form of construction and manufacture of theradiator shell the shell is formed from two sheet metal parts that arecut to shape, and portions of the edges of the parts are buttwelded.When they are thus integrally connected, they maintain each other in asubstantially definite relation-and so that por- 1930. Serial No.447,380.

tions thereof are located at desired angles relative to each other andwill lie against, substantially, the entire surfaceof the die-blankholder. The sheet metal between the edges, which is engaged by thedie-blank holder, is

shaped by the dies. Thus the shells may be formed to the required shapeby the use of the least'ainount of metal and by producingthe minimum ofthe draw of the metal when it is being die-pressed. The blank, beingformed of integrally connected parts, eliminates waste of the portionlocated within the inner edge of the metal'where a continuous ring, oroblong continuous part, is cut from sheetmetal. Also, by forming theband from two parts and butt-welding them, they may be so cut that whenthey are secured, they will roughly conform to the outlines of the edgesof the completed radiator shell, and, consequently, when their edgeportions are secured by the sheet metal holder, they may be shaped toproduce the required configuration by the dies with the least amount ofdraw, and least amount of abrasive action, thus protecting the surfaceof the metal to greatly reduce the finishing cost.

If desired, shells may be formed by shaping portions thereof separatelyandjoining them after they have been shaped. A portion of the shell maybe formed to cover theupper end and the sides of the radiator core,while the other portion may constitute a trim ex.- tending between theends of the first named portion. The said portions maybe securedtogether or secured to parts of the automobile to complete thedecorative features of the front of the automobile. Thus, the shell maybe formed by cutting substantially U- shaped strips from sheet metalhaving relatively' spreading legs and bending the strip to roughlyconform to the shape of the shell and securing the edges of the stripand shaping the central portions of the strip as may be'desire'd.

In the preferred method of formation of the radiator shells, a pluralityof parts are formed substantially truncated V-shaped or, moreaccurately, U-shaped, with 1e portions of each part inclined to each oter. The spread of the leg portions may be varied according-to the slopethat it is desired to 've the portions of the parts to one of the e gesof t e blank when they are bent roughly to conform to the shape of theradiator shell.

-The inner edges of the U-shaped strips, that are thus cut from thesheet, substantially conform to the outer edges whereby substantiallyall of the sheet, from which the parts joined together may be variedaccording to the final shape that is to be formed.

"To illustrate a practical application of the method embodying myinvention, I have selected a particular radiator shell as illustrativeof a shell that may be produced by the use of my invention and shalldescribe the shell, together with the steps used, in. its production, itbeing understood that variations in the method may be followed withinthe .limitations of the claims and their equivalent operations. Theshapes that are'formed by the use of my invention, in the formation ofthe particular radiator shell selected, is shown in the accompanyingdrawings.

Fig. 1 illustrates a sheet of metal from which a plurality of parts ofone form, used in making a plurality of radiator shells, may be out andthe figure indicates the use of practically all of the material of thesheet.

.Fig. 2 illustrates a strip from which parts a of another form maylikewise be cut in the formation of a pluralit of radiator shells and,likewise, indicates t e utilization of subthe line 7-7 indicated in Fig.6. Fig. 8 is astantially all of the metal of the strip. Fig.

3 illustrates the location of one of the parts,

cut from the sheet shown in Fig. 1, with reference to one of the partsout from the strip shown in Fig. 2, and shows the parts welded atportions of their edges to produce roughly the shape of the shell. Fig.4 illustrates the shell when it has been die-pressed to shape.

Fig. 5 is an end view of the shell when formed as shown in Fig. 4. Fig.6 illustrates the shell shown in Fig. 4 when it has been trimmed. Fig. 7is a view of a section of the shell shown in Fig. 6, taken on the planeof view of the shell when 'it has been punched and pierced to form holesalong'its edge to connect parts thereto, as, for example,cushion-members for parts of the hood of an automobile, and also forreceiving a neck of 'arradiator. Fig: 9 is aview of a section taken onthe plane of the line 99- indicated in ventionally the relation of theparts of the press and shows the relative positions of these-partsinadvance ofsecuring and shaping the strips of sheet metal. Fig. 11illustrates the positions of the partsof the press when the sheet metalhas been secured-in position in advance 'of shaping the central areas ofthe strip. Fig. 12 mdicates the positions of-the parts of the press whenthe shell has been shaped.

When the parts 1 have been cut from the sheet of metal 2, as indicatedby the dotted lines 3, and the parts 4 have been cut from the strip 5and from the scrap from sheet 2, as indicated by the dotted lines 6, inFigs. 1 and 2, they may be joined together, as illustrated in Fig. 3, toform blanks. The end edge portions 8, formed by cutting along the dottedline 7, are joined to turned up end portions 9 of the parts 4. The edgeportions 10 will then be substantially in line with the edge portions 11that form the end edges of the parts 4. Preferably, the corner portions12 of the parts are rolled inwardly to conform to the curvature of theupturned end portions 9 of the parts 4, substantially as indicated inFig. 3. When the parts 1 and 4 are thus joined together, they form acontinuous band, the portions of the part 1 being located inclined tothe plane of the edge 13, while the surface of the body portion 4 willbe slightly raised above the plane "of. the bottom edge, but will belocated substantially parallel to the said plane. The band that is thusformed will conform substantially to the die-plate holder which willgrip the edges of the band as formed.

The dies may then shape the portions located intermediate the edges ofthe connected parts, substantially as shown in Figs. 4 and 5. As shownin Fig. 9, the strip that makes up the body of-the shell is located. inposition in the holding die so that its edges will be located in contactwith the sheet metal blank holding parts 30 and 31, of the press 32which are spaced apart by the intermediate open area 48 across which thematerial will be bridged. The sheet metal part- 1 is bent at its cornersin the manner shown in Fig. 3, which roughly conforms to the shape ofthe shell and also which conforms to will nest in the holding members 30and 31. e M

The movable holding members 35 and 36 descend to grip the edge portionsof the blank as shown in Fig. 10. These members also have surfaces 37and 38 that conform to the surfaces of the edge portions of the blank sothat upon the descent of the members 35 and 36, the edge portions of theblank will be tions that are clamped between the said clamping membersof the press. The engaging faces of the members 3337 are flat and g aredisposedzsubstantially in the initial plane of the material whereas theengaging faces 34-38 are stepped and indented to effect a more securehold upon the material. As a result the intake of material through theholding members 3438, if any, involves a contraction of the materialbeyond the useable contoured area, whereas, the take of material, ifany, through the holding faces 33-37 occurs under an expanding orstretching tension which precludes the formation of Wrinkles. Whilethere may be some take of material from the larger margin, i. e.,through the holding members 3438,' the resulting die marks and wrinklesWill be disposed close to the edge of the produced form and in aposition where they will not be highly objectionable. The ram or maleshaping member 41 engages the unsupported portion of the flaring blankintermediate the holding members 3337 and 3438 in a directionsubstantially perpendicular to its general plane and in inclinedrelation to the surface of the blank. Since the blank originallyconforms roughly to the shape of the shell, the configuration producedby the stretching operation departs from'that of the shell blank by a.definite expansion. This eliminates deformation that occurs by reason ofsharply bending and subsequently stretching the bent portion and thuseliminates flaws and faults in the shell as finally formed, namely,creases that penetrate the metal, and wrinkles that are raised above thesurface. It is exceed ingly diflicult to remove the faults and markings,that is, creases or wrinkles that occur by bendin and stretching,particularly sharply ben ing and stretching, and by localizedstretching, that is, stretching more in' one portion of the sheet thanin adjoining portions. By thus shaping the blanks'so that they roughlyconform to the shape of the shell as finally produced and stretchin themetal without sharply bending, mar 'ngs of the metal will be entirelyavoided. Furthermore, by so shaping the blank and sec'ur ing it at itsedges, the central areas may be formed quite entirely by stretching.Thus, the shell is substantially entirely shaped without the use of afixed die and by the use ing of the metal.

of only a movable die. The blank being supported upon its longitudinalmargins only is stretched transversely of the strip of material formingthe flaring band .into conformity with the ram or shapingmember 41. Theexpanding or stretching of the material precludes the formation ofwrinkles and there is no excess material to be distributed, and sincethe stretching is effected in space no surface markings or draw linesdevelop. In the particular form of press shown'in the drawing, the metalis carried past the portion 34 by a projecting ridge or end 42, of thepart'41,

into the space 48 until the shape is formed. Y

A portion of the stretched sheet metal is finally compressed between thepart 43 of the holding member 31, and theend 42 and the edge of thesurface 44 of the former 41, giving to the completed form a final set.Thus, the shell is formed entirely by a stretchingoperation in advanceof any sharp bending move ment of the blank and the entire shell is produced by a gradual expansion of the entire area, as distinct from localdrawing or bend- There is a continuous camlike expansion movement of theshaping die, instead of a direct pressure exerted on the metal at rightangles to the surface of the blank before the metal has been stretched.This eliminates kinks or wrinkles and What is termed as tool markings.

The shell may then be trimmed to remove the portions 19 that have beengripped by the die-holder, leaving those portions of the shell thatconform to the required shape of the shell, as shown in Figs. 6 and 7.These parts may then befurther shaped tofit the members with which theyare associated, or mounted, in the automobile when assembled as a partof the automobile, such as to form the holes -18, the recess 20, and thehole 21. The depressed flange 22 may also be formed to receive theforward edge of the rhood of the automobile.

X a The narrow portion 23, formed from the part 4, will constitute atrim covering the lower edge of the radiator, while the other parts 24cover the forward and lateral edge portions of the radiator core orcooling section. I

for which it is particularly desirable, it is also applicable toproduction of other parts and articles such as automobile cowls,circuitous moldings and contoured frames, such as picture frames.Furthermore, while an endless or complete frame or'shell unithas beenillustrated some present automobile constructions employ an open endradiator shell as illustrated in my copending application Serial No.447,381 filed ofeven date-herewith,

and which is formed by the present method in thesame manner and by" thesame steps,

. merely omitting the part 4 and utilizing the method, however, is thatheretofore described pressure.

of joining the portions 1 andilinto an endless band before subjectingthem to forming It is to be understood that both sequences of operationas well as the formation of an open side U-shaped' unit are contemplatedwithin the legitimate and valid scope of the appended claims.

I claim:

1. The process of forminga radiator shell which consists in shapingsheet metal parts, welding edge portions of the parts to produce acontinuous flaring band roughly conforming to the shape of the shell,gripping opposite edges of the flaring band and stretching the portionsintermediate the opposite edges of the flaring band by projecting suchportions into space.

.2. The process of forming a radiator shell which consists in formingsheet metal parts, bending the ends of one of the parts in directionsinclined to the plane of the body of the said part into flaring arcuateformation and welding the terminal edge portions of the said part to endedge portions 'of the other of the said parts to produce a continuousband roughly conforming to the shape of the shell and applying pressureto the portions of the welded parts intermediate the opposite edges ofthe connected parts in a directionsubstantially perpendicular to thegeneral plane of the band and inclined flaring sides thereof.

3. The process of forming a radiator shell from sheet metal whichconsists in forming a blank of flaring curvilinear form, securing itsedge portions and stretching the portions of the blank intermediate itssecured edges by application of pressure in a direction substantiallyperpendicular to the general plane of the flared curvilinear blank.

. 4. The method of forming open framelike articles from sheet metalconsisting in forming an endless flaring band of material, gripping thelon 'tudinalmargins of the band in substantially fixed relation witheach other and applying pressure thereto intermediate its margins in adirection substantially perpendicular tothe general plane of the bandand inclined to theflaring surfaces thereof to transversely stretch theband into predetermined contoured form.

5. The herein describedmethod of forming sheet metal articles consistingin forming an endless flaring band of sheet material, gripping themarginal edges of the band and applying pressure to the bandintermediate to the vthe marginal edges and projectingthe engagedportion into space over a contoured form.

6. The herein described method of forming articles from sheet materialconsisting in forming a strip of material into a flaring curvilinearlybent blank, gripping the marginal edges of the strip and applyingpressure to the strip intermediate its gripped edges in a directionsubstantially perpendlcular to the general plane of the flaring blankand thereby stretching the strip of material transversely over acontoured form.

7. The herein described method of forming articles from sheet materialconsisting in forming a strip of material into a flaring curvilinearlybent form, gripping the longitudinal marginal edges of the strip andsimultaneously projecting into space in different directions differentportions of the strip by pressure applied substantially perpendicular tothe plane of the longitudinal margins of the bent strip intermediate itsing 'forma'tion, cutting a second flat blank section, marginally unitingthe blank sections whereby the second section interconnects theterminals of the first section into endless formation, and subjectingsuch endless flaring composite-blank to radially expansive forminpressure.

10. The hereln described method of formingarticles from sheet materialincluding cutting from a stock sheet a flat strip of material ofsubstantially truncated V shape,

bending the strip to curvilinear flaring form and subjecting the bentstrip to forming pressure in a direction substantially perpendicular tothe general plane of the curvilinear flaring formation.

11. .The herein described method of forming articles from sheet materialincluding forming a strip of material into a curvedly bent flaringformation, subjecting the bent strip to transversely expanding pressurethroughout substantially its entire extent and effecting a take ofmaterial from the inner and shorter marginal edge under expansivetension and from the outer and longer margin under contractive tension.

12. The method which consists in bending a blank strip to locate one ofthe side edges thereof approximately in a plane and to flare the bentstrip gripping the sides and end portion of the bent sheet metal blankat its respective edges and forming and stretchingthe unsecured areathereof into the required shape by pressure applied in a directionsubstantially perpendicular to the said plane of one of its grippededges to one side only thereof.

l3. The process of forming a concavo-convex sheet metal unit, whichconsists in cutting from a sheet of material a truncated V-shaped parthaving its inner and outer edges substantially parallel to each other,and cutting from a sheet of material a second part, welding the ends ofthe first named part to portions of the edge of the last named part forforming a circuitous flaring band roughly conforming to the shape of thefinished unit and transversely stretching the band intermediate itsopposite edges into the desired shape.

14: The method of forming a structure embodying two transverselycontoured portions integrally united into an open frame like unit,including bending a blank portion into a flaring U-shaped formation toform the end and sides of the unit, and disposing across the open end ofthe U-shaped formation a second blank portion to form the other end ofthe unit and simultaneously subjecting both portions to formingpressure.

15. The process of forming radiator shell which includes cutting fromasheet of mate- I rial a plurality of substantially truncated V-shapedparts having the inner edge of one part and outer edge of the adjacentpart substantially conforming to each other with the convex margin ofone part extending within the reentrant side of the adjacent part,bending each such part intosubstantially U-.

shaped flaring formation and subsequently contouring the flaring sidesthereof transversely by subjecting the bent parts to pressure applied inthe same direction simultw neously tothe substantially parallel sidesand transverse portion of such U-shaped flaring formation. i

16. The process of forming a radiator shell from a strip of sheet metal,including bending the strip into a substantially U-'- shaped'flaringformation to conform roughly to the shape of the shell to be formed, anddistending portions thereof intermediate its edge portionsby'application of pressure'in' the same direction simultaneously to the.respective side and transverse portions of the U-shaped formation.

17. The herein described method of forming articles from ,sheet materialconsisting in forming a strip of material into a flaring curvilinearlybent blank, bringing the edges into planes yieldingly securing themarginal edges of the strip by gri ping the inner and outer marginaledges o the flaring blank,

and applying expanding pressure to the strip intermediate the securedmargins and substantially perpendicular to the planes thereof, therebvdistorting the flared blank into 18. The herein described method of forming articles from sheet material including forming a strip of materialinto a flaring curvilinear formation, grippingthe marginal edgesthereof, and shaping the article by simultaneously expanding the stripin difli'erj ent directions by pressure applied in one direction to thecurved strip intermediate its gripped edges.

19. The method of forming an open frame like unit from sheet material,including providing two blank portions, disposing said portions ininclined relation one to the other in a forming apparatus in theapproximate relation to each other which the parts occupy in thecompleted unit, gripping the opposite marginal edges of the respectiveportions and subjecting the areas of the relatively disposed blankportions intermediate their gripped margins to simultaneous formingpressure by action ofa forming member common to both blank portions.

20. The method of forming an open frame like unit from sheet material,including providing two blank portions interconnected in the finalstructure into an integral unit, disposing the portions in inclinedrelation to each other in the approximate positions they occupy in. thecompleted unit, holding the tion by application of forming pressurethereto.

In Witness whereof I have hereunto my name to this specification. v

- GEORGE E. IRELAND.

signed iao

